The purpose of Core A is to ensure scientific progress by providing adequate scientific and administrative leadership to the program and provide adequate financial oversight. This will be accomplished by extensive review of scientific progress during monthly meetings of all the lab groups and smaller meetings held by subgroups. Scientific direction and research results will be subject to intense, yet constructive, criticism by investigators within the P01, and by an outside advisory board. We strongly believe that our extensive collaborative approach promoted by Core A is unique. Indeed, this program represents the nucleating group for Bay Area investigators studying intracellular pathogens and innate immunity. The Specific Aims are: 1. Ensure Scientific Progress, and II. Implement Financial Management and Administrative Support. To facilitate interactions among investigators, two-hour joint lab meetings will continue to be held monthly at the UCSF Mission Bay Campus. The monthly meetings consist of introductory discussions, two scientific presentations, and post-meeting discussions. A scientific advisory board will be maintained to oversee research progress and provide objective criticism of the programs. The board will meet once every other year and provide a report. To facilitate interactions between the cores and the projects, each of the labs will designate representative to Core B (mouse and ENU core). A website will help coordinate sharing of data, protocols, and Powerpoint presentations from the monthly meeting. Additional mechanisms to promote interactions include shared interviews of potential post-doctoral fellows and a joint seminar program between UCB and UCSF. Core A will provide the financial oversight for the program project and for each research plan and core. UC Berkeley will act as the central administrator of the program's financial activities. The Administrative Assistant will facilitate communication via the appropriate contacts at UCSF such that UC Berkeley can monitor and expedite financial arrangements and also attend to any problems. Project Leaders will receive monthly reports of their financial activities and have ample opportunities to resolve questions and assess the planning of purchases for their research.